Pretty simple question. We know it's gonna go on for a while. It might even go on for longer than Oda himself wants to keep going. This is a manga that's on the way of becoming the highest-selling shonen of all time, and there's no way in hell Oda's editors are gonna let him walk away easily. At the very least, it'll go on for 10 more years.
Keeping that in mind, and taking into consideration all you've liked and haven't liked about the series in the last 10 years, how long do you see yourself still being entertained by it before you simply get bored?